Fuel injector



Jan. 8, 1946. L Q F CH 2,392,374

FUEL INJECTOR Filed Oct. 23, 1943 9 F INVENTOR.

Patented Jan. 8, 1946 UNITED STATES PATENT OFFICE FUEL INJECTOR Louis 0. French, Milwaukee, Wis. Application October 23, 1943, Serial No. 507.362

7 Claims.

The invention relates to fuel injectors for internal combustion engines. Directional spray nozzles are usually of the the open type with the spray passages at some at the end of ,a long small passage which allow fuel deposits to build up and interfere with the proper spraying of the. charges. One object of this invention is to overcome the above objections by providing a directional spray valve with control valve opening in the-direction of fuel flow which may be relatively cheaply made as it requires in stem seal and in which the nozzle forms a stop for the valve andhas the spray passages arranged immediately adjacent but outside of the seat ofithevalve andjwhich because of the arrangementoffthe parts may be readilyclea'ned," aidnozzle alsopreferably having a bottom open- 1 ing to'permit flushing-fol? -th e space adjacent the directional spray'passages to cool the valve and nozzle and prevent deposits of-carbonize'zd' fuel that might interfere with' th'e movement of the valve.

A further object of ith ej.invention is to provide a spray valve which {may be. readily" cooled if desired.

The invention further -consists in ithe several features hereinafter set forth and more particularly defined by claims at the conclusion hereof.

In the drawing: v p Fig. 1 is an enlarged vertical sectional view through a'fuelinjector valve embodying the invention; l v

Fig. 2 is an enlarged view showing certain modifications. I

' In the dra'win'g,,; the numeral 3 designates l a nozzle member, 4 a controlvalve, '5 a valve seatmember, 6a 'casingmember, 'Iya flanged nut for clamping the-nozzle assembly against a pipe member of a separate pump system o'r'thepuinp barrel 8 of a unit inje'cton' lhe parts 5 and Ii f rm a valvehhousinga v Y 1 The valve 'seat;.member 5 has a cylindrical extension 9 centering-it "in a fcentrally disposed .fuel supply bore. Iliin' the casing 8 and a shoulder similar to Fi Y thousandths' of an inch, {This II which abuts in fluid-tight engagement with the reduced inner end of said casing. The member 5 has a. centrally disposed valve guide bore II, a seat 13 at the inner end of said bore and a surface I 4 tapering from the seat to said shoulder II, the included angle of the sides of said surface being preferably about sixty degrees. The sloping of this surface facilitates the placing of the spray passages close to the valve seat.

The valve 4 has a stem'slidably mounted in the bore l2 and a head held against the seat l3' preferably by a tension spring I5 whose lower hooked end extends through a hole IS in the valve stem and whose outer-eyed end isanchored to the casing 6 by a pin I! that at its outer ends rests on an annular surface formed by a counter-bore 18 at the outer end of the bore Iii in said casing. The head of. the valve 4 tapers to a point l9 whose tapered surface iscoaxial and co-angular with the surface I4.

The'nozzle member 3 has a bore 20 to receive the reducedportion of the casing Band a tapered bore 2| extending from said bore 20 and cotapered with the taper 'of' the surface II to provide afluid seal therebetween' andwhich' in Fig. 1 extends to the tip. 1The3head. of-= the valve is spaced'a short distance-from.,.the n'oz'zleto provide, a small lift," for example} W I I earance space may be obtained by-makingfthe diameter of the base of the "point l9 sli'ghtlyless li'ani-the outer diameter of:the valve seat;

Directional spray openings .i-ziare formed in the nozzle member-3"in 'linegjwithjcr'closely ad-' jacent the valve seat.bacIeYof-ItheT head of the -valve in itsopen position. opening 23 is also preferably. provided atthebottdmfehd of thebore 2|. v

With this construction whfi ithe fuel-pressure acting on the valve '4' overcomes-the tension of j. the spring l5,.-the valve opens outwardly until its head strikes the end of. the nozzle-3. During the time the valve. moves to its stopposition some fuel-will pass between the valve andthe lower theopening 23, and'also'duringfthis time and while the valve is in its open position, fuel will end of, the nozzle and-be;'-sprayed out through also pass through the spray openings 22 into the cylinder of. the engine, 'these spray Openings being v ,disposed at the desired angle relative to the head and piston of the engine to project the fuel 1 into the desired localityof thecombustion' chamber and being circumferentialiy disposed relative to each other to distribute-the charge throughout i the air in the combustion chamber, the position mitento thirtyof the openings 22 varying with the type of en- 1 As in the first construction, the valve this opening during the time the valve is moving to open position will flush over and thus act to cool the head of the valve and the parts of the nozzle adjacent thereto, and passage of fuel through this opening will also prevent carbonized fuel depositing in the end of said nozzle member and interfering with the movement of the valve. In full open position the valve head engages the bore 2| and fuel flows only through the openings 22.

The construction shown in Fig. 2 is generally similar to that just described except that the casing member 24 and the nozzle member 25 are arranged to provide a cooling fluid chamber 26 between them and a pin 2'! on the point 28 of the valve 29 is adapted tof project down into the opening 30 to form a pintle-type nozzle and an annular spray during the time said valve 29 moves from its closed to its open position.

For forming the chamber 26 I provide the casing 24 with an annular recess 32, and the lower flange portion 33 is radially notched or splined at spaced intervals as indicated at 34 to allow the cooling liquid to contact the lower portion of the seat member 35- though allowing the unnotched portions of said flange to act as a guide for the bore 25' of the nozzle member 25.

The outer edge 36 of the nozzle member 25 is conically inclined, and the lower spaced side 31 of the flange 38 of the casing 24 is similarly inclined to receive a packing 39' of lead, neoprene, graphite impregnated asbestos cord or other suitable material which may be distorted when in the pump barrel 45, suitable means being provided to position these passages in alinement.

The clearance determining the lift of the valve 29 is shown as provided by a tapered bore 46 which is longitudinally displaced a short distance from the coaxial and cotapered bore 41, thus permitting the valve to open the amount of this displacement. This displacement of the head- I engaging here may also .be used in conjunction with a valve head of smaller diameter than the seat to provide the valve lift distance. 29 is held in a normally closed position by a tension spring 48 which is anchored at one end to the upper end of the valve stem and at its other end receives a pin 49 which seats at its ends on the counterbore 59 in the casing 24. The nozzle member 25 has the spray openings communicating with the bore 46 adjacent the seat of the valve seat member 35 and through which the fuel issues when the valve 29 engages the bore 46 in its open position.

The operation of this injector valve is the same as the first form except that the pin 21 moves into the hole or opening 36 during the operation of the valve and the fuel from the supply pump is continually circulated through the chamber 26 to aid in cooling the nozzle in addition to the usual cooling of the nozzle casing by parts of the cylinder head.

By the term outwardly opening valve I mean a valve which opens in the direction of fuel flow or toward the space into which the fuel is injected.

I desire it to be understood that this invention is not to be limited to any particular form or arrangement of parts except in so far as such limitations are included in the claims.

What I claim as my invention is:

1. In a fuel nozzle, the combination of a valve housing having a seat and a conically tapered surface extending back from said seat, an outwardly opening fluid pressure operated valve seated on said seat and having a head coaxial and of similar taper to said surface, a spring to hold said valve in normally closed position, a nozzle member having a tapered surface fitting said first named conically tapered surface and having a conically tapered surface portion similar to that of said valve head and engaged thereby in the open position ofsaid valve and provided with spray openings adjacent the outer edge of said seat and back of the head of said valve when the valve is in its open position.

2. In a fuel nozzle, the combination of a pair of concentric interfitting sleeves having a cooling space formed between them, a seat member in fluid tight engagement with the lower end portions of said sleeves, the outer of said sleeves having an end forming a nozzle tip, an outwardly opening fluid pressureioperated valve seated on said seat member and having a head engageable with said tip when the valve is in its open position, said tip having spray openings adjacent the seat for the valve and back of said head when the valve is in its open position, means sealing the upper ends of said sleeves from the escape of cooling fiuid, and means for circulating cooling fluid through said cooling space.

3. In a fuel injector, the combination of a valve housing having a fuel passage and a seat, an outwardly opening fluid pressure controlled valve normally seated on saidseat, a nozzlemember having a wall portion forming a stop engaging the head of said valve when said valve is in its open position to limit the lift of the valve to not more than a thirty-thousandths of an inch and having spray passages in said wall portion whose inlets communicate with the space formed between the seat for the valve and seating surface of the valve when the valve is in its open position and are so close to said'seat that the distance from the seat that the fuel travels before entering said spray passages is not more than the lift of the valve.

4. In a fuel injector, the combination of a valve housing having a fuel passage and a seat, an outwardly opening fluid pressure controlled valve.

normally seated on said seat and having a seating surface and a tapered head projecting beyond said seating surface, means to hold said valve in normally closed position, a nozzle member having a tapered bore portion coaxial with the head of said valve and of similar taper and whose side walls are in sealing engagement with the head of the valve when the valve is in its open position and provided with spray openings leading from said bore portion adjacent the outer edge of said seat and whose inlets are spaced from said seat a distance not greater than the lift of the valve whenthe valve is in its open position.

5. In a fuel injector, the combination of a valve housing having a fuel passage and a seat, an outwardly opening fluid pressure controlled valve normally seated on said seat, a nozzle member having a wall portion forming a stop spaced a short distance from the valve in its closed position and engaging the outer end of the valve when said valve is in its open position and having spray passages in said wall portion adjacent the outer edge of said seat, the distance of the inlets of said spray passages from said seat being not greater than the lift of the valve.

6. In a fuel injector, the combination of a valve housing having a fuel passage and a seat, an outwardly opening fluid pressure controlled valve having a seat portion normally seated on said seat and a head portion projecting beyond said seat portion, a nozzle member having a bore into which said valve head projects and from which it is spaced a short distance in the closed position of the valve and by which the opening movement of the valve is limited, said nozzle member having spray passages leading from said bore adjacent the outer edge of said seat and whose inlets are spaced from said seat a distance not greater than the lift of the valve, the walls is in its open position to confine the fuel flow from the seat opening to said spray passages to the small clearance area then existing above the seat portion of the valve.

'7. In a fuel injector, the combination of a valve housing having a fuel passage and a seat, an outwardly opening fluid pressure controlled valve normally seated on said seat, a nozzle member having spray openings adjacent said seat and back of the head of the valve in its open position and having a part spaced from the head of the valve in its closed position and engaging the head of the valve to prevent fuel passing around said head in the open position of the valve and provided with a spray passage communicating with said seat through the space between said part and head of valve and disposed beyond said part and through which fuel may flow during the opening of the valve and be cut off from said seat by said part engaging said head in the ful open position of said valve.

LOUIS O. FRENCH. 

